? CH3NH2 CH3-O-CH3 CH3CH2OH CH3CH2F Both CH3CH2F and CH3CH2OH
The Correct Answer and Explanation is:
The correct answer is CH3NH2, CH3CH2OH.
Explanation:
Hydrogen bonding occurs when a hydrogen atom is covalently bonded to a highly electronegative atom, such as oxygen, nitrogen, or fluorine, and is in close proximity to another electronegative atom with a lone pair of electrons.
Let’s analyze each substance:
- CH3NH2 (Methylamine):
- In CH3NH2, the hydrogen atom is bonded to nitrogen, which is highly electronegative. Nitrogen also has a lone pair of electrons that can interact with the hydrogen atoms of neighboring molecules, forming hydrogen bonds.
- Therefore, CH3NH2 will have hydrogen bonds between molecules.
- CH3-O-CH3 (Dimethyl ether):
- Here, the oxygen is bonded to two methyl groups (CH3). Oxygen has lone pairs, but there is no hydrogen directly bonded to oxygen, and thus, no hydrogen bonding can occur between the molecules.
- Therefore, CH3-O-CH3 will not have hydrogen bonds.
- CH3CH2OH (Ethanol):
- In CH3CH2OH, the hydroxyl group (-OH) contains a hydrogen atom bonded to an oxygen atom. Oxygen, being electronegative, pulls electron density from the hydrogen, making it capable of forming hydrogen bonds with the lone pairs of electrons on oxygen or nitrogen in neighboring molecules.
- Therefore, CH3CH2OH will have hydrogen bonds between molecules.
- CH3CH2F (Ethyl fluoride):
- In CH3CH2F, the hydrogen atoms are bonded to carbon, and fluorine is present in the molecule. Although fluorine is electronegative and could form hydrogen bonds with other molecules, the hydrogen is not directly bonded to fluorine. The molecule does not meet the criteria for hydrogen bonding, as no hydrogen is attached to either nitrogen, oxygen, or fluorine.
- Therefore, CH3CH2F will not have hydrogen bonds between molecules.
In conclusion, CH3NH2 and CH3CH2OH will exhibit hydrogen bonding between their molecules, while the others will not.
